go_id,ontology,go_term,term_definition,evidence GO:0005634,CC,nucleus,"A membrane-bounded organelle of eukaryotic cells in which chromosomes are housed and replicated. In most cells, the nucleus contains all of the cell's chromosomes except the organellar chromosomes, and is the site of RNA synthesis and processing. In some species, or in specialized cell types, RNA metabolism or DNA replication may be absent.",IEA GO:0005737,CC,cytoplasm,"All of the contents of a cell excluding the plasma membrane and nucleus, but including other subcellular structures.",IDA GO:0005815,CC,"microtubule organizing center","An intracellular structure that can catalyze gamma-tubulin-dependent microtubule nucleation and that can anchor microtubules by interacting with their minus ends, plus ends or sides.",IDA